Patent US3663958A successfully refreshed from Google Patents.
US3663958A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Voltage monitoring device having a pair of differential amplifiers
Assignee: Individual
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Filing: 1970-06-24
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Granted: 1972-05-16
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Expires: 1990-06-24
Abstract
Abstract The output of an electrical power source is continuously monitored by voltage comparing circuits to which a reference voltage is applied through a low impedance driver. The reference voltage is compared with adjustably reduced values of the variable voltage of the source being continuously sampled to establish upper and lower voltage limits. When these limits are exceeded, a resettable alarm circuit is triggered into operation.
Inventors
- 👤 Harold E Crane
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 14:10
CPC Classifications
G; G01; G01R; G01R19/00; G01R19/165; G01R19/16533; G01R19/16538; G01R19/16547
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
241 words
A voltage monitoring circuit connected to a source of variable voltage comprising a D.C. voltage line, a pair of voltage comparing circuit sections connected to said voltage line, each of said circuit sections including a voltage dividing network having an adjustable potentiometer, an amplifier transistor having a base connected to the potentiometer, an output collector and an input emitter and a signal transmitting transistor having an input base and an output emitter, one of said circuit sections further including inverter means connecting the output collector of the amplifier transistor to the input base of the signal transmitting transistor for developing an undervoltage signal, the output collector of the amplifier transistor in the other of the circuit sections being directly connected to the input base of the signal transmitting transistor for developing an overvoltage signal, an OR gate connected to the output emitters of said signal transmitting transistors for conducting said undervoltage or overvoltage signals, alarm means connected to the OR gate for producing an alert in response to either of said signals, reference voltage establishing means connected to the voltage line, an emitter follower connecting the reference voltage establishing means to the input emitter of one of the amplifier transistors, a voltage reducing resistor connecting the emitter follower to the input emitter of the other of the amplifier transistors and a common emitter resistor connected between ground and one of said input emitters and in series with said voltage reducing resistor.
Claim 2
Dependent Claim
241 words
A voltage monitoring circuit connected to a source of variable voltage comprising a D.C. voltage line, a pair of voltage comparing circuit sections connected to said voltage line, each of said circuit sections including a voltage dividing network having an adjustable potentiometer, an amplifier transistor having a base connected to the potentiometer, an output collector and an input emitter and a signal transmitting transistor having an input base and an output emitter, one of said circuit sections further including inverter means connecting the output collector of the amplifier transistor to the input base of the signal transmitting transistor for developing an undervoltage signal, the output collector of the amplifier transistor in the other of the circuit sections being directly connected to the input base of the signal transmitting transistor for developing an overvoltage signal, an OR gate connected to the output emitters of said signal transmitting transistors for conducting said undervoltage or overvoltage signals, alarm means connected to the OR gate for producing an alert in response to either of said signals, reference voltage establishing means connected to the voltage line, an emitter follower connecting the reference voltage establishing means to the input emitter of one of the amplifier transistors, a voltage reducing resistor connecting the emitter follower to the input emitter of the other of the amplifier transistors and a common emitter resistor connected between ground and one of said input emitters and in series with said voltage reducing resistor.
Claim 3
Dependent Claim
111 words
In combination with a variable source of voltage, at least two voltage comparing circuits connected to said source for monitoring the same, gate means connected in common to said circuits for conducting output signals from either of the circuits, voltage driver means connected in common to the circuits to form a differential amplifier with each of the circuits, and means connecting the voltage driver means to the source for establishing a reference voltage against which the variable voltage of the source is measured in each of the voltage comparing circuits to produce said output signals therefrom when upper and lower voltage limits are exceeded by the variable voltage of said source.
Claim 4
Dependent Claim
111 words
In combination with a variable source of voltage, at least two voltage comparing circuits connected to said source for monitoring the same, gate means connected in common to said circuits for conducting output signals from either of the circuits, voltage driver means connected in common to the circuits to form a differential amplifier with each of the circuits, and means connecting the voltage driver means to the source for establishing a reference voltage against which the variable voltage of the source is measured in each of the voltage comparing circuits to produce said output signals therefrom when upper and lower voltage limits are exceeded by the variable voltage of said source.
Claim 5
Dependent Claim
110 words
The combination of claim 2 wherein each of said voltage comparing circuits includes a current conducting device having input, output and control elements, means connecting the input elements of the circuits to the voltage driver means for applying the reference voltage to the voltage comparing circuits, means connecting the output elements to the source for continuously sampling the variable voltage thereof, separate adjusting means connecting the source to the control elements for establishing said voltage limits beyond which the variable voltage causes switching of the current conducting devices between conductive and non-conductive states, and means for producing said output signals in response to said switching of the current conducting devices.
Claim 6
Dependent Claim
37 words
The combination of claim 3 wherein one of the current conducting devices is held in a non-conductive state and the other in a conductive state while the variable voltage of said source is between said voltage limits.
Claim 7
Dependent Claim
26 words
The combination of claim 4 including common indicator means connected to the gate means for registering the output signals from either of said voltage comparing circuits.
Claim 8
Dependent Claim
40 words
The combination of claim 5 including switching level control means connected in common to the current conducting devices and the voltage driver means for substantially eliminating the affect of temperature variations on the voltage limits established by the adjusting means.
Claim 9
Dependent Claim
40 words
The combination of claim 3 including switching level control means connected in common to the current conducting devices and the voltage driver means for substantially eliminating the affect of temperature variations on the voltage limits established by the adjusting means.
Claim 10
Dependent Claim
26 words
The combination of claim 1 including common indicator means connected to the gate means for registering the output signals from either of said voltage comparing circuits.
Claim 11
Dependent Claim
41 words
The combination of claim 1 including switching level control means connected in common to the voltage comparing circuit sections and the voltage driver means for substantially eliminating the affect of temperature variations on the voltage limits established by the adjusting means.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-05-16 | 1975-11-15 | 1976-05-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-05-16 | 1979-11-15 | 1980-05-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-05-16 | 1983-11-15 | 1984-05-16 | $7700.00 | Window Closed / Lapsed |